Systems and methods for gradually adjusting a control parameter associated with a cochlear implant system

ABSTRACT

An exemplary sound processor included in a cochlear implant system associated with a patient 1) receives, from a fitting system while the sound processor is communicatively coupled to the fitting system, a command that sets a control parameter associated with the cochlear implant system to an initial value and data representative of a target value associated with the control parameter, 2) detects a decoupling of the sound processor from the fitting system, the decoupling resulting in the sound processor being in a non-fitting state, and 3) gradually adjusts, while the sound processor is in the non-fitting state, the control parameter from the initial value towards the target value in accordance with an adaption time course associated with the control parameter. Corresponding systems and methods are also disclosed.

BACKGROUND INFORMATION

When a cochlear implant of a cochlear implant system is initiallyimplanted in a patient, and during follow-up tests and checkupsthereafter, it is usually necessary to fit the cochlear implant systemto the patient. For example, during a fitting session, a clinician mayutilize a fitting system to set various control parameters associatedwith (e.g., that govern an operation of) the cochlear implant systemand/or otherwise configure the cochlear implant system for operation.

One of the control parameters that is often set during a fitting sessionfor a cochlear implant patient is a most comfortable level (“M level”).An M level represents a stimulation current level required to achievecomfortable loudness to the patient. In other words, the M levelrepresents a stimulation current level, which, when applied to a givenset of one or more electrodes associated with the M level, produces asensed perception of sound by the patient that is moderately loud, orcomfortably loud, but not so loud that the perceived sound isuncomfortable.

An M level is typically determined by sequentially increasing thestimulation current level for the patient until the patient reports acomfortably loud sound on a subjective loudness scale. Because the Mlevel anchors the patient's mapping function, defines the patient'selectrical dynamic range (thereby impacting a host of perceptualattributes, such as loudness, sound-field-thresholds, spectral contrast,etc.), and is often used to derive other control parameters, accuratelydetermining the M level is highly desirable.

It is a common observation that M levels are often under-fit (i.e., setto be lower than what the patient can actually tolerate) during thefitting process. This is at least in part due to the fact that thepatient's tolerance of electrical stimulation is strongly influenced bysound exposure. Many cochlear implant patients have not had much, ifany, exposure to loud sounds prior to being implanted with a cochlearimplant. Hence, these patients may not initially be able to toleraterelatively high M levels, even though their ability to tolerate high Mlevels may increase over time as they are exposed to more loud sounds.

Unfortunately, however, M levels are only adjusted during fittingsessions (i.e., when the patient visits a clinic). This means that the Mlevels are held constant in between the fitting sessions, even thoughthe ability of a patient to tolerate different electrical stimulationlevels may fluctuate over time as the patient is exposed to differentlevels of sound.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate various embodiments and are a partof the specification. The illustrated embodiments are merely examplesand do not limit the scope of the disclosure. Throughout the drawings,identical or similar reference numbers designate identical or similarelements.

FIG. 1 illustrates an exemplary cochlear implant system according toprinciples described herein.

FIG. 2 illustrates a schematic structure of the human cochlea accordingto principles described herein.

FIG. 3 shows an exemplary configuration in which a fitting system iscommunicatively coupled to the cochlear implant system shown in FIG. 1according to principles described herein.

FIG. 4 illustrates exemplary components of a sound processor accordingto principles described herein.

FIG. 5 shows a graphical representation of an adaption time course for acontrol parameter according to principles described herein.

FIG. 6 shows an exemplary look-up table that includes datarepresentative of an adaption time course for a particular controlparameter according to principles described herein.

FIG. 7 shows a graphical representation of an adaption time course for acontrol parameter according to principles described herein.

FIG. 8 illustrates an exemplary method of gradually adjusting a controlparameter associated with a cochlear implant system.

DETAILED DESCRIPTION

Systems and methods for gradually adjusting a control parameterassociated with a cochlear implant system are described herein. As willbe described below, a sound processor included in a cochlear implantsystem associated with a patient may receive, from a fitting systemwhile the sound processor is communicatively coupled to the fittingsystem, a command that sets a control parameter associated with thecochlear implant system to an initial value and data representative of atarget value associated with the control parameter. The sound processormay subsequently enter a non-fitting state by being decoupled from thefitting system. While in the non-fitting state, the sound processor maygradually adjust the control parameter from the initial value towardsthe target value in accordance with an adaption time course associatedwith the control parameter.

As an example, a fitting system may be used by a clinician to initiallyfit a cochlear implant system to a patient subsequent to the patientbeing implanted with a cochlear implant. To this end, the clinician mayconnect a sound processor included in the cochlear implant system to thefitting system (e.g., by way of a clinician's programming interface(“CPI”) device). While the sound processor is connected to the fittingsystem, the clinician may perform one or more procedures to determine aninitial value for an M level associated with the patient. As mentioned,this initial value for the M level may be under-fit (i.e., less than atarget value for the M level that the patient should subsequently beable to tolerate after being exposed to sound over the course of acertain amount of time). To facilitate patient adaption to the targetvalue of the M level, the clinician may use the fitting system totransmit, to the sound processor, a command that sets the M level to theinitial value, data representative of a target value associated with theM level, and data representative of an adaption time course associatedwith the M level. As will be illustrated below, the adaption time coursemay specify a time course during which the M level is to be graduallyadjusted by the sound processor from the initial value towards thetarget value.

After the fitting session is over, the sound processor may be decoupledfrom the fitting system (e.g., by being disconnected from the CPIdevice). The sound processor may detect this decoupling and, inresponse, enter a non-fitting state in which the sound processor mayoperate normally (e.g., by locking to the cochlear implant and, whilelocked, directing the cochlear implant to apply electrical stimulationrepresentative of audio signals received and processed by the soundprocessor).

While in the non-fitting state, the sound processor may gradually adjustthe M level from the initial value towards the target value inaccordance with the adaption time course associated with the M level.For example, the sound processor may adjust the M level such that the Mlevel trends upward towards the target value. As will be describedbelow, incremental increases and decreases in the M level may occurduring the trending upward towards the target value based on one or moreother time-based and environmental-based factors.

The gradual adjustment of the M level may cease once the M level hasreached the target level. Additionally or alternatively, the gradualadjustment of the M level may cease in response to user input providedby the patient.

By gradually adjusting a control parameter associated with a cochlearimplant in this manner, the systems and methods described herein mayfacilitate patient adaption to a target value for the control parameterwithout requiring the patient to attend multiple fitting sessions. Thismay save the patient (and the clinician) time and resources. Moreover,the gradual adjustment of a control parameter as described herein mayoptimize cochlear implant system performance and allow for more accuratesound representation to the patient. Other benefits of the presentsystems and methods will be made apparent herein.

As used herein, a “control parameter” associated with a cochlear implantsystem may refer to any setting, stimulation parameter, and/or otherparameter that governs an operation of one or more components includedin the cochlear implant system. For example, a control parameter may bean M level, a threshold level (“T level”), an input dynamic range(“IDR”), a stimulation rate, and/or a pulse width. As described above,an M level represents a stimulation current level required to achievecomfortable loudness to the patient. A T level represents a minimumstimulation current level that produces a sensed perception of sound bythe patient. IDR represents the difference (in SPL) between a soundamplitude producing T level stimulation and a sound amplitude producingM level stimulation. Stimulation rate refers to how many stimulationpulses per second may be applied by way of a given set of one or moreelectrodes. Pulse width refers to a width of each stimulation pulse thatis applied by way of the given set of one or more electrodes.

Each of the control parameters described herein may be stimulationchannel-specific. As used herein, a “stimulation channel” refers to aset of one or more electrodes by way of which electrical stimulation maybe applied to a stimulation site within a cochlear implant patient.Because there may be multiple stimulation channels within a cochlearimplant system, there may be multiple instances of a particular controlparameter. For example, there may be a plurality of M levels eachassociated with a different stimulation channel. Alternatively, a singleinstance of a control parameter may be associated with all of thestimulation channels within a cochlear implant system.

FIG. 1 illustrates an exemplary cochlear implant system 100. As shown,cochlear implant system 100 may include various components configured tobe located external to a patient including, but not limited to, amicrophone 102, a sound processor 104, and a headpiece 106. Cochlearimplant system 100 may further include various components configured tobe implanted within the patient including, but not limited to, acochlear implant 108 and a lead 110 (also referred to as anintracochlear electrode array) with a plurality of electrodes 112disposed thereon. As will be described in more detail below, additionalor alternative components may be included within cochlear implant system100 as may serve a particular implementation. The components shown inFIG. 1 will now be described in more detail.

Microphone 102 may be configured to detect audio signals presented tothe patient. Microphone 102 may be implemented in any suitable manner.For example, microphone 102 may include a microphone that is configuredto be placed within the concha of the ear near the entrance to the earcanal, such as a T-MIC™ microphone from Advanced Bionics. Such amicrophone may be held within the concha of the ear near the entrance ofthe ear canal by a boom or stalk that is attached to an ear hookconfigured to be selectively attached to sound processor 104.Additionally or alternatively, microphone 102 may be implemented by oneor more microphones disposed within headpiece 106, one or moremicrophones disposed within sound processor 104, one or morebeam-forming microphones, and/or any other suitable microphone as mayserve a particular implementation.

Sound processor 104 (i.e., one or more components included within soundprocessor 104) may be configured to direct cochlear implant 108 togenerate and apply electrical stimulation (also referred to herein as“stimulation current”) representative of one or more audio signals(e.g., one or more audio signals detected by microphone 102, input byway of an auxiliary audio input port, etc.) to one or more stimulationsites associated with an auditory pathway (e.g., the auditory nerve) ofthe patient. Exemplary stimulation sites include, but are not limitedto, one or more locations within the cochlea, the cochlear nucleus, theinferior colliculus, and/or any other nuclei in the auditory pathway. Tothis end, sound processor 104 may process the one or more audio signalsin accordance with a selected sound processing strategy or program togenerate appropriate stimulation parameters for controlling cochlearimplant 108. Sound processor 104 may include or be implemented by abehind-the-ear (“BTE”) unit, a body worn device, and/or any other soundprocessing unit as may serve a particular implementation. For example,sound processor 104 may be implemented by an electro-acousticstimulation (“EAS”) sound processor included in an EAS system configuredto provide electrical and acoustic stimulation to a patient.

In some examples, sound processor 104 may wirelessly transmitstimulation parameters (e.g., in the form of data words included in aforward telemetry sequence) and/or power signals to cochlear implant 108by way of a wireless communication link 114 between headpiece 106 andcochlear implant 108. It will be understood that communication link 114may include a bi-directional communication link and/or one or morededicated uni-directional communication links.

Headpiece 106 may be communicatively coupled to sound processor 104 andmay include an external antenna (e.g., a coil and/or one or morewireless communication components) configured to facilitate selectivewireless coupling of sound processor 104 to cochlear implant 108.Headpiece 106 may additionally or alternatively be used to selectivelyand wirelessly couple any other external device to cochlear implant 108.To this end, headpiece 106 may be configured to be affixed to thepatient's head and positioned such that the external antenna housedwithin headpiece 106 is communicatively coupled to a correspondingimplantable antenna (which may also be implemented by a coil and/or oneor more wireless communication components) included within or otherwiseassociated with cochlear implant 108. In this manner, stimulationparameters and/or power signals may be wirelessly transmitted betweensound processor 104 and cochlear implant 108 via a communication link114 (which may include a bi-directional communication link and/or one ormore dedicated uni-directional communication links as may serve aparticular implementation).

Cochlear implant 108 may include any type of implantable stimulator thatmay be used in association with the systems and methods describedherein. For example, cochlear implant 108 may be implemented by animplantable cochlear stimulator. In some alternative implementations,cochlear implant 108 may include a brainstem implant and/or any othertype of active implant or auditory prosthesis that may be implantedwithin a patient and configured to apply stimulation to one or morestimulation sites located along an auditory pathway of a patient.

In some examples, cochlear implant 108 may be configured to generateelectrical stimulation representative of an audio signal processed bysound processor 104 (e.g., an audio signal detected by microphone 102)in accordance with one or more stimulation parameters transmittedthereto by sound processor 104. Cochlear implant 108 may be furtherconfigured to apply the electrical stimulation to one or morestimulation sites within the patient via one or more electrodes 112disposed along lead 110 (e.g., by way of one or more stimulationchannels formed by electrodes 112). In some examples, cochlear implant108 may include a plurality of independent current sources eachassociated with a channel defined by one or more of electrodes 112. Inthis manner, different stimulation current levels may be applied tomultiple stimulation sites simultaneously (also referred to as“concurrently”) by way of multiple electrodes 112.

FIG. 2 illustrates a schematic structure of the human cochlea 200 intowhich lead 110 may be inserted. As shown in FIG. 2, the cochlea 200 isin the shape of a spiral beginning at a base 202 and ending at an apex204. Within the cochlea 200 resides auditory nerve tissue 206, which isdenoted by Xs in FIG. 2. The auditory nerve tissue 206 is organizedwithin the cochlea 200 in a tonotopic manner. Relatively low frequenciesare encoded at or near the apex 204 of the cochlea 200 (referred to asan “apical region”) while relatively high frequencies are encoded at ornear the base 202 (referred to as a “basal region”). Hence, eachlocation along the length of the cochlea 200 corresponds to a differentperceived frequency. Cochlear implant system 100 may therefore beconfigured to apply electrical stimulation to different locations withinthe cochlea 200 (e.g., different locations along the auditory nervetissue 206) to provide a sensation of hearing.

FIG. 3 shows an exemplary configuration 300 in which a fitting system302 is communicatively coupled to cochlear implant system 100 by way ofsound processor 104. Fitting system 302 may be implemented by anysuitable combination of computing and communication devices including,but not limited to, a fitting station, a personal computer, a laptopcomputer, a handheld device, a mobile device (e.g., a mobile phone), aclinician's programming interface (“CPI”) device, and/or any othersuitable component or computing device as may serve a particularimplementation. In some examples, fitting system 302 may provide one ormore graphical user interfaces (“GUIs”) (e.g., by presenting the one ormore GUIs by way of a display screen) with which a clinician or otheruser may interact.

Fitting system 302 may be selectively coupled to sound processor 104 inany suitable manner. While coupled to sound processor 104, fittingsystem 302 may be used to perform various types of fitting procedureswith respect to cochlear implant system 100. For example, fitting system302 may program sound processor 104 to operate in accordance with one ormore sound processing programs, adjust one or more control parametersassociated with cochlear implant system 100 (e.g., by transmitting acommand to sound processor 104 that sets a particular control parameterto a particular value), and/or perform any other suitable operation withrespect to cochlear implant system 100.

FIG. 4 illustrates exemplary components of sound processor 104. It willbe recognized that the components shown in FIG. 4 are merelyrepresentative of the many different components that may be included insound processor 104 and that sound processor 104 may include additionalor alternative components as may serve a particular implementation.

As shown in FIG. 4, sound processor 104 may include a processingfacility 402 and a storage facility 404, which may be in communicationwith one another using any suitable communication technologies.Processing facility 402 and/or storage facility 404 may include or beimplemented by a computing device or processor configured to perform oneor more of the functions described herein.

Storage facility 404 may maintain control parameter data 406, adaptiontime course data 408, and log data 410 received, generated, and/or usedby processing facility 402. Control parameter data 406 may include, butis not limited to, an initial value of a control parameter, a targetvalue of the control parameter, and/or any other data associated withthe control parameter. Adaption time course data 408 may include datarepresentative of an adaption time course associated with a particularcontrol parameter. Log data 410 may include data representative of ahistory of a gradual adjustment of a control parameter. Storage facility404 may maintain additional or alternative data as may serve aparticular implementation.

Processing facility 402 may perform various operations with respect tocochlear implant system 100 and/or fitting system 302. For example,processing facility 402 may process an audio signal detected bymicrophone 102, and, based on the processing, direct cochlear implant108 to generate and apply electrical stimulation representative of theaudio signal to one or more stimulation sites within the patient by wayof one or more electrodes 112. As another example, processing facility402 may detect a coupling of sound processor 104 to fitting system 302,and, in response, direct sound processor 104 to enter a “fitting state”in order to facilitate programming of sound processor 104 by fittingsystem 302. Processing facility 402 may subsequently detect a decouplingof sound processor 104 from fitting system 302, and, in response, directsound processor to enter a “non-fitting state” in which sound processor104 may operate normally. Various specific operations of processingfacility 402 associated with gradually adjusting a control parameterwill now be described.

As mentioned, it may be desirable to gradually and automatically adjusta control parameter associated with cochlear implant system 100 inbetween fitting sessions. For example, a cochlear implant patient may beinitially able to tolerate a relatively low M level during a fittingsession and shortly thereafter. However, after being exposed to soundsfor an extended period of time (e.g., days or weeks), the patient may beable to tolerate a relatively higher M level. Hence, it may be desirableto dynamically increase the M level for the patient as the patientbecomes more accustomed to sound without requiring the patient toparticipate in repeated fitting sessions (which would typically requirethe patient to make multiple trips to the clinic).

To this end, during a fitting session in which sound processor 104 iscommunicatively coupled to fitting system 302, a clinician and/or thefitting system 302 itself may determine an initial value and a targetvalue for a control parameter. The initial value may be determined inany suitable manner (e.g., in accordance with subjective feedback fromthe patient). Likewise, the target value may be determined in anysuitable manner (e.g., by eliciting and measuring a stapedius reflex(“eSRT”) and/or any other objective measure, setting the target value toautomatically be a predetermined percentage (e.g., twenty percent)higher than the initial value, and or in any other manner). The targetvalue may be greater than or less than the initial value depending onthe particular control parameter. For example, if the control parameteris an M level, the target value may be greater than the initial value.Alternatively, if the control parameter is pulse width, the target valuemay be less than the initial value.

Fitting system 302 may transmit a command to sound processor 104 thatsets the control parameter to the initial value. Fitting system 302 mayalso transmit data representative of the target value to sound processor104. Processing facility 402 may receive the command that sets thecontrol parameter to the initial value and the data representative ofthe target value in any suitable manner.

In some examples, the clinician and/or the fitting system 302 itself mayalso specify an adaption time course associated with the controlparameter. Fitting system 302 may transmit data representative of theadaption time course to sound processor 104. Processing facility 402 mayreceive the data representative of the adaption time course and storethis data within storage facility 404 (e.g., in the form of adaptiontime course data 408). Alternatively, sound processor 104 may bepre-programmed with data representative of the adaption time course.

The adaption time adaption time course may specify a time course duringwhich the control parameter is to be gradually adjusted by soundprocessor 104 from the initial value towards the target value. Toillustrate, FIG. 5 shows a graphical representation 500 of an adaptiontime course for a control parameter. In graphical representation 500,line 502 represents the value of a particular control parameter as afunction of time. As shown, as time progresses, the value of the controlparameter gradually increases from an initial value towards a targetvalue. In the particular example of FIG. 5, the gradual increase islinear. However, it will be recognized that other adaption time coursesmay specify that the control parameter increases and/or decreases in anyother manner (e.g., the rate of increase for the control parameter mayincrease as time progresses).

Data representative of the adaption time course may be received andmaintained by sound processor 104 in any suitable manner. For example,data representative of the adaption time course may be maintained bysound processor 104 in the form of a look-up table. To illustrate, FIG.6 shows an exemplary look-up table 600 that includes data representativeof an adaption time course for a particular control parameter (e.g., anM level) and that may be maintained by sound processor 104.

As shown, look-up table 600 specifies a plurality of time increments anda series of control parameter values. Each time increment represents anamount of elapsed time with respect to a start time (which maycorrespond to a time that the sound processor 104 is decoupled fromfitting system 302, a time that the sound processor 104 first locks to acochlear implant subsequent to being decoupled from fitting system 302,and/or a time associated with any other event as may serve a particularimplementation).

Each control parameter value included in look-up table 600 represents avalue that the control parameter is to be set to at each time increment.For example, look-up table 600 indicates that the control parameter isto be set by processing facility 402 to 1000 microamps at a timeincrement of zero hours (i.e., 1000 microamps is the initial value).After 12 hours have elapsed, the control parameter is to be increased byprocessing facility 402 to 1010 microamps. Likewise, after 24 hours haveelapsed, the control parameter is to be increased by processing facility402 to 1020 microamps. The control parameter may be gradually increasedby processing facility 402 in this manner until the control parametermaxes out at the target value (which, in this example, is 1080 microampsand occurs at a time interval of 96 hours). By gradually increasing thecontrol parameter in this manner, processing facility 402 may allow thepatient to adapt to each increased value without even noticing that thecontrol parameter is being adjusted.

Once the command to set the control parameter to the initial value andthe data representative of the target value are transmitted to soundprocessor 104 during a fitting session, sound processor 104 may bedecoupled from fitting system 302. Processing facility 402 may detectthis decoupling in any suitable manner. In response to the decoupling,processing facility 402 may direct sound processor 104 to enter anon-fitting state. While the sound processor 104 is in the non-fittingstate, processing facility 402 may gradually adjust the controlparameter from the initial value towards the target value in accordancewith the adaption time course associated with the control parameter.This may be performed in any suitable manner.

For example, processing facility 402 may adjust the control parameter inaccordance with the data included in look-up table 600. To this end,processing facility 402 may track an elapsing of time (e.g., beginningwith the decoupling of sound processor 104 from fitting system 302) andincrementally adjust the control parameter to a next value included inthe series of values in response to an occurrence, within the elapsingof time, of each time increment included in the plurality of timeincrements. For example, in response to an elapsing of 12 hours,processing facility 402 may adjust the control parameter from 1000microamps to 1010 microamps. This process may continue until the controlparameter maxes out at the target value.

Processing facility 402 may track the elapsing of time in any suitablemanner. For example, processing facility 402 may track the elapsing oftime by tracking a total number of clock cycles that elapse subsequentto a starting event (e.g., an initial locking of sound processor 104 tocochlear implant 108). Additionally or alternatively, processingfacility 402 may utilize a clock that tracks time in terms of any othersuitable increment (e.g., seconds, minutes, hours, and/or days).

In some examples, processing facility 402 may adjust the controlparameter while sound processor 104 is locked to cochlear implant 108and abstain from adjusting the control parameter 104 while soundprocessor 104 is not locked to cochlear implant 108. As used herein, thesound processor 104 may be “locked” to cochlear implant 108 while soundprocessor 104 is actively communicating with cochlear implant 108. Forexample, sound processor 104 may lock to cochlear implant 108 eachmorning when the patient turns “on” sound processor 104, but may not belocked to cochlear implant 108 after the patient turns the soundprocessor 104 “off” (e.g., at night while the patient sleeps).Processing facility 402 may detect that sound processor 104 is or is notlocked to cochlear implant 108 in any suitable manner.

In cases where processing facility 402 only adjusts the controlparameter while sound processor 104 is locked to cochlear implant 108,the adaption time course may not take into account time periods duringwhich sound processor 104 is not locked to cochlear implant 108. Inother words, the time intervals shown in look-up table 600 may only betracked while sound processor 104 is locked to cochlear implant 108. Insome alternative embodiments, the adaption time course does take intoaccount time periods during which sound processor 104 is not locked tocochlear implant 108. In these alternative embodiments, the timeintervals shown in look-up table 600 are tracked regardless of whethersound processor 104 is locked to cochlear implant 108.

In some examples, processing facility 402 may adjust the controlparameter until the control parameter reaches the target value.Processing facility 402 may detect that the control parameter hasreached the target value and, in response, cease the adjustment of thecontrol parameter. At any point before the control parameter reaches thetarget value, the patient may provide user input (e.g., by pressing abutton on the sound processor 104) representative of a command to ceaseadjusting the control parameter. Processing facility 402 may detect thisuser input and, in response, cease the adjustment of the controlparameter. Such user input may be provided, for example, if the userexperiences pain and/or discomfort as a result of the gradual adjustmentof the control parameter.

Processing facility 402 may take into account one or more othertime-based and/or environmental-based factors while gradually adjustingthe control parameter towards the target value. For example, processingfacility 402 may take into account a time of day while graduallyadjusting the M level (or any other control parameter) towards thetarget value. This is because electrical stimulation experienced by thepatient early in the morning after a night of device deactivation ismost likely perceived as being very loud compared to the samestimulation received later in the day when the patient has had moresubstantial exposure to sound. This is akin to a stereo soundinguncomfortably loud when it is turned on in the morning from a state thatit was in during a loud party the previous night.

Hence, processing facility 402 may incrementally decrease the M leveleach morning when sound processor 104 locks to cochlear implant 108 sothat sounds do not appear to be overly loud to the patient. Processingfacility 402 may then increase the M level as the time of day progressesin accordance with the adaption time course. This is illustrated in FIG.7, which shows a graphical representation 700 of an adaption time coursethat has been modified to take into account the time of day. Line 702represents the value of a particular M level as a function of time. Asshown, as time progresses, the value of the M level gradually trendsupwards from an initial value towards a target value. However, FIG. 7shows that at times t₁ and t₂, which correspond to times in the morningsof subsequent days when the sound processor 104 first locks to thecochlear implant 108, processing facility 402 incrementally decreasesthe M level.

As mentioned, processing facility 402 may additionally or alternativelytake into account one or more other environmental-based factors whilegradually adjusting the control parameter towards the target value. Forexample, processing facility 402 may take into account an amount ofsound exposure to the patient during a determined time period whilegradually adjusting the M level (or any other control parameter) towardsthe target value.

For example, processing facility 402 may detect an amount of soundexposure to the patient within a predetermined time period and performthe gradual adjustment of the control parameter from the initial valuetowards the target value in accordance with the detected amount of soundexposure to the patient within the predetermined time period. Thepredetermined time period may be any suitable amount of time as mayserve a particular implementation. For example, the predetermined timeperiod may be relatively short when taking into account instantaneoussound exposure to the patient. Alternatively, the predetermined timeperiod may be relatively long when taking into account average soundexposure to the patient.

Processing facility 402 may detect the amount of sound exposure to thepatient in any suitable manner. For example, processing facility 402 maydetect the amount of sound exposure to the patient by detecting a soundlevel (e.g., an amplitude) of an audio signal received by microphone 102and average the sound level over the predetermined time period.

In some examples, if the detected amount of sound exposure is above afirst threshold within the predetermined time period, processingfacility 402 may increase the control parameter (e.g., by an incrementalamount). Similarly, if the detected amount of sound exposure is below asecond threshold (which may be the same as or less than the firstthreshold) within the predetermined time period, processing facility 402may decrease the control parameter (e.g., by an incremental amount).

For example, if the patient enters and stays in an environment that hasrelatively loud sounds (e.g., a noisy restaurant), processing facility402 may at least temporarily increase an M level associated with thepatient. In some examples, the M level (or any other control parameter)may be temporarily adjusted (e.g., increased) only after the patient hasbeen in the relatively loud environment for a predetermined amount oftime (e.g., a few hours, a day, etc.). This would ensure that thepatient has had sufficient exposure to the current value of the M levelbefore further adjusting the M level. When the patient leaves the loudenvironment and enters a relatively quiet environment (e.g., thepatient's home), processing facility 402 may decrease the M levelassociated with the patient (e.g., after a predetermined amount oftime). It will be recognized that these incremental increases anddecreases in response to changing sound exposure may be performed on topof (i.e., in addition to) the underlying gradual adjustment of thecontrol parameter in accordance with the adaption time course.

In some examples, processing facility 402 may log a history of thegradual adjustment of the control parameter. Processing facility 402 maythen detect a coupling of sound processor 104 to fitting system 302subsequent to logging the history, and, in response, transmit datarepresentative of the logged history to fitting system 302. A clinicianmay then utilize fitting system 302 to perform one or more analysisoperations with respect to the logged history in order to furtheroptimize the control parameter.

In some examples, a cochlear implant system may include a bilateralconfiguration wherein separate cochlear implants are implanted for bothears of the patient. In this configuration, the patient may utilize afirst sound processor for the first ear and a second sound processor forthe second ear. In some examples, control parameters associated witheach sound processor may be gradually adjusted in accordance with thesystems and methods described herein. The sound processors maycoordinate the adjustment of the control parameters (e.g., by way of awireless link between the sound processors.

In some alternative examples, a cochlear implant system may be includedin a bimodal configuration wherein the patient is fitted with a cochlearimplant for his/her first ear and a hearing aid for his/her second ear.In this configuration, control parameters associated with both thecochlear implant system and the hearing aid may be gradually adjusted inaccordance with the systems and methods described herein. The adjustmentmay be coordinated in any suitable manner.

FIG. 8 illustrates an exemplary method 800 of gradually adjusting acontrol parameter associated with a cochlear implant system. While FIG.8 illustrates exemplary steps according to one embodiment, otherembodiments may omit, add to, reorder, and/or modify any of the stepsshown in FIG. 8. One or more of the steps shown in FIG. 8 may beperformed by sound processor 104 and/or any implementation thereof.

In step 802, a sound processor receives a command that sets a controlparameter to an initial value and data representative of a target valueassociated with the control parameter. The sound processor may receivethe command and data from a fitting system while the sound processor iscommunicatively coupled to the fitting system. Step 802 may be performedin any of the ways described herein.

In step 804, the sound processor detects a decoupling of the soundprocessor from the fitting system, the decoupling resulting in the soundprocessor being in a non-fitting state. Step 804 may be performed in anyof the ways described herein.

In step 806, the sound processor gradually adjusts, while in thenon-fitting state, the control parameter from the initial value towardsthe target value in accordance with an adaption time course associatedwith the control parameter. Step 806 may be performed in any of the waysdescribed herein.

In the preceding description, various exemplary embodiments have beendescribed with reference to the accompanying drawings. It will, however,be evident that various modifications and changes may be made thereto,and additional embodiments may be implemented, without departing fromthe scope of the invention as set forth in the claims that follow. Forexample, certain features of one embodiment described herein may becombined with or substituted for features of another embodimentdescribed herein. The description and drawings are accordingly to beregarded in an illustrative rather than a restrictive sense.

What is claimed is:
 1. A cochlear implant system comprising: a cochlearimplant configured to be implanted within a patient; and a soundprocessor configured to receive, from a fitting system during a fittingsession, a command that sets a most comfortable level (“M level”) to aninitial value, the initial value of the M level representing a firststimulation current level required for the cochlear implant to produce asensed perception of sound that is comfortably loud for the patientduring the fitting session, and a target value for the M level, thetarget value for the M level representing a second stimulation currentlevel that is greater than the first stimulation current level and thatis required for the cochlear implant to produce a sensed perception ofsound that is comfortably loud for the patient at a time subsequent tothe fitting session; store an adaption time course that specifies aplurality of time increments and a series of values between the initialvalue and the target value; detect a decoupling of the sound processorfrom the fitting system, the decoupling resulting in the sound processorbeing in a non-fitting state; gradually adjust, while the soundprocessor is in the non-fitting state and subsequent to the fittingsession, the M level from the initial value towards the target value inaccordance with the adaption time course; and direct the cochlearimplant to apply stimulation having the gradually adjusted M level tothe patient; wherein the sound processor is configured to graduallyadjust the M level from the initial value towards the target value by:tracking an elapsing of time beginning with the decoupling of the soundprocessor from the fitting system; and incrementally adjusting the Mlevel to a next different value included in the series of values inresponse to an occurrence, within the elapsing of time, of each timeincrement included in the plurality of time increments.
 2. The cochlearimplant system of claim 1, wherein the sound processor is configured toreceive data representative of the adaption time course associated fromthe fitting system while the sound processor is communicatively coupledto the fitting system.
 3. The cochlear implant system of claim 1,wherein the sound processor is further configured to: gradually adjustthe M level from the initial value towards the target value by detectingwhen the sound processor is locked to the cochlear implant and adjustingthe M level while the sound processor is locked to the cochlear implant;and abstain from adjusting the M level while the sound processor is notlocked to the cochlear implant.
 4. The cochlear implant system of claim1, wherein the sound processor is further configured to: detect that theM level has reached the target value; and cease, in response to the Mlevel reaching the target value, the adjustment of the M level.
 5. Thecochlear implant system of claim 1, wherein the sound processor isfurther configured to: detect user input representative of a command tocease adjusting the M level before the M level reaches the target value;and cease, in response to the user input, the adjustment of the M level.6. The cochlear implant system of claim 1, wherein the gradualadjustment of the M level from the initial value towards the targetvalue is further performed by the sound processor in accordance with atime of day.
 7. The sound processor of claim 6, wherein the processingfacility gradually adjusts the M level in accordance with the time ofday by incrementally decreasing the M level when the sound processorfirst locks to a cochlear implant during the day; and increasing the Mlevel as the time of day progresses.
 8. The cochlear implant system ofclaim 1, wherein the sound processor is further configured to: detect anamount of sound exposure to the patient within a predetermined timeperiod; and further perform the gradual adjustment of the M level fromthe initial value towards the target value in accordance with thedetected amount of sound exposure to the patient within thepredetermined time period.
 9. The cochlear implant system of claim 8,wherein the sound processor is further configured to: increase the Mlevel if the detected amount of sound exposure is above a firstthreshold within the predetermined time period; and decrease the M levelif the detected amount of sound exposure is below a second thresholdwithin the predetermined time period.
 10. The cochlear implant system ofclaim 1, wherein the sound processor is further configured to: receive,from the fitting system during the fitting session, a command that setsan additional control parameter other than the M level to an additionalinitial value, and data representative of an additional target value;and gradually adjust, while the sound processor is in the non-fittingstate and subsequent to the fitting session, the additional controlparameter from the additional initial value towards the additionaltarget value in accordance with an additional adaption time; wherein theadditional control parameter comprises at least one of a threshold level(“T level”), an input dynamic range (“IDR”), a stimulation rate, and apulse width.
 11. The cochlear implant system of claim 1, wherein thesound processor is further configured to log a history of the gradualadjustment of the M level.
 12. The cochlear implant system of claim 11,wherein the sound processor is further configured to: detect acommunicative coupling of the sound processor to the fitting systemsubsequent to the gradual adjustment of the M level; and transmit, whilethe sound processor is communicatively coupled to the fitting systemsubsequent to the gradual adjustment of the M level, data representativeof the logged history to the fitting system.
 13. A system comprising: acochlear implant configured to be implanted within a patient; and asound processor configured to control the cochlear implant; and afitting system configured to transmit, during a fitting session, acommand that sets a most comfortable level (“M level”) to an initialvalue, the initial value of the M level representing a first stimulationcurrent level required for the cochlear implant to produce a sensedperception of sound that is comfortably loud for the patient during thefitting session, a target value for the M level, the target value forthe M level representing a second stimulation current level that isgreater than the first stimulation current level and that is requiredfor the cochlear implant to produce a sensed perception of sound that iscomfortably loud for the patient at a time subsequent to the fittingsession, and an adaption time course that specifies a plurality of timeincrements and a series of values between the initial value and thetarget value; wherein the sound processor is configured to receive thecommand, the target value, and the adaption time course from the fittingsystem, detect a decoupling of the sound processor from the fittingsystem, gradually adjust, subsequent to being decoupled from the fittingsystem and subsequent to the fitting session, the M level from theinitial value towards the target value in accordance with the adaptiontime, and direct the cochlear implant to apply stimulation having thegradually adjusted M level to the patient; wherein the sound processoris configured to gradually adjust the M level from the initial valuetowards the target value by: tracking an elapsing of time beginning withthe decoupling of the sound processor from the fitting system; andincrementally adjusting the M level to a next different value includedin the series of values in response to an occurrence, within theelapsing of time, of each time increment included in the plurality oftime increments.
 14. The system of claim 13, wherein: the soundprocessor is further configured to log a history of the gradualadjustment of the M level, and transmit, while the sound processor isagain communicatively coupled to the fitting system subsequent to thegradual adjustment of the M level, data representative of the loggedhistory; and the fitting system is further configured to receive thedata representative of the logged history, and perform one or moreanalysis actions with respect to the logged history.
 15. A methodcomprising: receiving, by a sound processor during a fitting sessionwith a fitting system, a command that sets a most comfortable level (“Mlevel”) to an initial value, the initial value of the M levelrepresenting a first stimulation current level required for a cochlearimplant to produce a sensed perception of sound that is comfortably loudfor the patient during the fitting session, and a target value for the Mlevel, the target value of the M level representing a second stimulationcurrent level that is greater than the first stimulation current leveland that is required for the cochlear implant to produce a sensedperception of sound that is comfortably loud for the patient at a timesubsequent to the fitting session; storing, by the sound processor, anadaption time course that specifies a plurality of time increments and aseries of values between the initial value and the target value;detecting, by the sound processor, a decoupling of the sound processorfrom the fitting system, the decoupling resulting in the sound processorbeing in a non-fitting state; gradually adjusting, by the soundprocessor while the sound processor is in the non-fitting state andsubsequent to the fitting session, the M level from the initial valuetowards the target value in accordance with the adaption time course;and directing the cochlear implant to apply stimulation having thegradually adjusted M level to the patient; wherein the gradual adjustingcomprises: tracking an elapsing of time beginning with the decoupling ofthe sound processor from the fitting system; and incrementally adjustingthe M level to a next different value included in the series of valuesin response to an occurrence, within the elapsing of time, of each timeincrement included in the plurality of time increments.
 16. The methodof claim 15, further comprising receiving data representative of theadaption time course from the fitting system while the sound processoris communicatively coupled to the fitting system.
 17. The method ofclaim 15, further comprising: receiving, by the sound processor duringthe fitting session, a command that sets an additional control parameterother than the M level to an additional initial value, and datarepresentative of an additional target value; and gradually adjusting,by the sound processor while the sound processor is in the non-fittingstate and subsequent to the fitting session, the additional controlparameter from the additional initial value towards the additionaltarget value in accordance with an additional adaption time course;wherein the additional control parameter comprises at least one of athreshold level (“T level”), an input dynamic range (“IDR”), astimulation rate, and a pulse width.